PLEASE HELP! GUINEA KEET sTUCK IN SHELL

okay this is my situation,
This is my first time hatching guinea fowl keets. I have 27 keets in a fan-forced incubator the humidity is ranging between 70 and 80% and temp is at 37.5. the keets started hatching on their 24th day of incubation and i now have 18 completely hatched and it is day 27.

One of the keets started pipping externally yesterday morning and he still isn't out. he has fully zipped around the shell but just won't come out. every now and again the egg will shake and i can hear him cheeping. I need to know if i should help him out.

there are other pipped eggs and some in the middle of hatching and I'm afraid if I open the lid of the incubator, to get the egg out or to get the already hatched chicks the humidity might drop and the ones that are hatching might get stuck inside the membrane.

Is it just the membrane that has not quite broken and stopping the keet hatching? Opening is a risk and I can't say you should or should not open. Opening may or may not shrink wrap there is no way to tell for sure. Many do open and have no problems others do and have problems. These are your eggs and you have to decide. If it's just a bit of membrane stopping the keet you could gently split it if there are no blood vessels to let the keet finish hatching. If you do don't pull the keet out just put it back in the bator and let it finish up on its own. I've had this before with chicks with varying results, one was ok and made it and I'm afraid the other didn't. My thoughts are it couldn't hatch on its own as it was a weak chick in the first place and didn't have the strength to get through the membrane.

Have you done a staggered hatch as 3 days is quite a while for them to be hatching over?

The keet that has broken through parts of the membrane and pipped all the way around the shell, but not all of it. The rest of the keets have been trying to give him a hand themselves by pecking at the shell and membrane and trying to tear it away. yesterday he was making lots of noise but it sounded like he was struggling. he kept on rocking in the egg but wouldn't push out the the round end like the others did.

the first keet that hatched pipped while it was still in the egg tray on day 23 so for some reason he was early, but all the rest mostly came today and yesterday. I put 8 eggs in a day after I started incubating the rest so my hatch will be a bit staggered but they have already pipped so hopefully they will be out soon.

As for the keet thats stuck if he doesn't some how get out during tonight I will help him out tomorrow.

Also the keet that is stuck right now, accidently knocked a huge piece of shell of the side of his egg while he was pipping. I think that might also be the reason he's struggling to get out because the larger area of exposed membrane would have dried out pretty quickly.